The Henry Ford Museum in Dearborn, Michigan is something of an ode to American engineering.

Henry Ford enjoyed collecting pieces of history during his lifetime, and in 1929, his collection

became a museum. Nowadays, about a century later, it contains over 26 million pieces in its archives.

That's a lot of history. You can find JFK's presidential limousine, the very bus, Rosa Parks

Road when she famously refused to give up her seat, the chair from the theater where

President Abraham Lincoln was shot and killed.

And of course, there's Henry Ford's defining invention, the Model T. Car. But amongst all these

artifacts, there's one that was so precious to Ford that he kept it a secret until he died. It's a test tube that contains nothing,

or at least it looked like nothing. It actually contained Thomas Edison's last breath.

There's something about this item as an object as a thing in and of itself that seems very, very pertinent.

Because on the one hand, it's incredibly ordinary.

It's like the most basic piece of chemical apparatus.

That's Mark Ruther, Vice President of Historical Resources and Chief Curator at the museum.

But also, you realize that the ordinary, oft times, is not so ordinary at all if you can look at it in the right way. It's unexpected. It sits

rather quietly in a case and provokes a good number of questions. I'm Jerome Campbell, and this

is Atlas Obscura, a celebration of the world's strange, incredible, and wondrous places.

Today, we're going to learn about the true value

of Ford's most private possession

and how it preserves a friendship

and a world transformed

by both titans of industry.

More after this. The story of Henry Ford's friendship with Thomas Edison began long before the two ever met.

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